Rotary engines



Sept. 11, 1956 G. ORLOFF 2,762,307

ROTARY ENGINES Filed Sept. 2,-1952 2 Sheets-5heet 1 INVENTOR Sept. 11,1956 G. ORLOFF 2,762,307

ROTARY ENGINES Filed Sept. 2, 1952 2 Sheets-Sheet 2 fig. 4.

N VEN TOR wfi M mechanism is reduced to a minimum.

United States Patent ROTARY ENGINES George Orloir, Gloucester, England,assignor to British Messier Limited, Gloucester, England, a British com-P y Application September 2, 1952, Serial No. 307,453

Claims priority, application Great Britain September 5, 1951 7 Claims.(Cl. 103-49) This invention comprises improvements in or relating torotary engines.

It is an object of the invention to provide a small highpressure rotaryengine capable of operating a hydraulic pump; the invention includes thecombination of such an engine and pump in one casing. It is a furtherobject of the invention to provide a valve gear for such an engine whichis capable of operating efliciently at high speed without vibration andwith minimum leakage of gas.

According to the present invention a combined prime mover and hydraulicpump unit is provided, having in combination a plurality of motorcylinders grouped around an axis and extending longitudinally relativelythereto, a group of pump cylinders similarly grouped around the axis,pistons in the motor and pump cylinders each motor piston being directlyengaged with one of the pump pistons, a swash plate rotatable about saidaxis and operatively connected to the motor pistons to be driventhereby, a spindle for the swash plate extending along said axis, arotary valve coaxial with and driven by the spindle, and portscontrolled by said rotary valve communicating with the motor cylinders.

The motor cylinders may be located in a motor cylinder body parallelwith and grouped around the axis thereof, which body is hollowed out atone end to receive and enclose a pump body containing the pumpcylinders.

The rotary valve is preferably a cylindrical plug valve havingperipheral ports and is located in a cylinder head of the motor cylinderbody, in which head are ports connecting the valve with each of themotor cylinders in turn.

Alternatively, the motor cylinder block may have a valve face at therear end having ports therein communieating with the cylinders, and therotary valve bears upon the valve face and has a pressure face on theopposite side thereof from the valve-face, a main port through the valvefrom the pressure face to the valve face, which port lies on one side ofthe axis and co-operates with the ports in the valve face and abalancing port lying on the other side of the axis and also extendingthrough the valve but opening on to the valve face at a difierent radiusfrom the radius of the ports.

In the above described constructions the swash plate has nothing todrive but the valve and the friction of the If the hydraulic pump andthe rotary engine are located in the same casing and the pressure faceof the valve is supplied with pressure fluid, such as high pressure airor stream, the result will be that high pressure continuous supply ofhydraulic fluid will be available from the pump in an apparatus ofminimum size and weight. The valve can be balanced mechanically as wellas being pressure balanced and thus the apparatus will operate at highspeed without vibration and with minimum leakage.

The following is a description by way of example of certainconstructions in accordance with the invention, reference being made tothe accompanying drawings in which:

' of the end face of the five pistons Figure 1 is a cross section uponthe line 11 of Figure 2 through a rotary engine in accordance with theinvention,

- Figure 2 is a longitudinal section of the same,

Figure 3 is a longitudinal section through a preferred construction,

Figure 4 is a section through the cylinder head of the constructionshown in Figure 3, and

Figure 5 is an end view of the cylinder head showing the ports therein.

Referring first to the construction shown in Figures 1 and 2, a casing11 is provided which is broadly speaking of cylindrical form and whichis hollowed out at each end, leaving however sutlicient metal in themiddle to form a cylinder block 12. The cylinder block is bored out withfive cylinder bores extending parallel to the axis of the casing andequidistant therefrom. The cylinder bores do not extend right throughthe cylinder block but stop short of one end to which each of themisconnected by means of a port 13, and the port end of the cylinder blockis made flat to act as a valve face 14. As viewed endwise the ports eachhave the shape of a flattened oval with the longest dimension arrangedradially and their inner ends close to but spaced a little from theaxis, sufficiently to allow between them a bore to receive a valvespindle coaxial with the casing. The outer edges of the ports are spacedby a substantial distance from the periphery of the valve face, thusleaving an outer area of the valve face which is uninterrupted by ports.

Within each cylinder is a trunk-shaped piston 15 provided with suitablepacking rings and having a forward end which is hollowed out to receivea ball-shaped head of a hydraulic plunger 16. The piston around the stemof the plunger has a conical end face and the inner part bear upon aring 17, the rim of which is Lshaped in cross section and receives aball race 18. The inner ring of the ball race rests in an inclinedseating on a member 19 keyed to the valve stem 20 and the valve stempasses through the cylinder block to a valve member 21 which works onthe valve face. The angle ring, ball race and seating member form aswash plate which is driven by the pistons and serves to rotate thevalve stem.

The valve on the valve stem forms an enlarged head which is large enoughto overlie the ports in the valve face and which has a valve pressureface on the side remote from the valve face.

It will be recollected that the casing 11 was bored out at each end. Thebore of the casing at the end which contains the valve face on thecylinder block, is of course large enough to contain the rotating valvehead and it also receives a .plug 22 which fits its interior closely andis provided with a sealing ring and is held in place by a split wirering 23 concentric with a plug and recessed into the wall of the bore ofthe casing but not sufiiciently to prevent it overlying at the back ofthe plug. The plug carries a projecting nipple 24, coaxial with itself,and adapted to be connected to a source of high pressure fluid such ashigh pressure superheated steam. Through the plug there extends apassage toward the valve head and within the plug just above thepressure face on the valve end there is a sliding sealing ring 25 whichis urged into contact with the pressure face by a spring in the plug.Thus, if pressure is applied through the bore in the plug this pressurewill have access to a limited circular area enclosed within the sealingring and located on the head of the valve. This pressure, if unbalanced,would cause the valve to bear with a heavy force on the valve face ofthe cylinder block. The space Within the plug which surrounds the headof the valve is connected to a lateral exhaust port 26 on the side ofthe casing.

There extends through the valve from the pressure face to the face whichis in contact with the valve face of the cylinder block a port 27 forthe supply of pressure fluid to the cylinders. This port lies to oneside of the axis of the valve and is so shaped, and timed in relation tothe swash plate, as'to deliver pressure fluid to the cylinders duringthe time in which the pistons therein are moving away from the cylinderhead toward the outer end of their stroke. The under side of the valveis hollowed out from side to side on the opposite side of the axis fromthe port 27 just described so that it acts as an exhaust port and gasesfrom the cylinders on the return stroke of the plungers pass direct tothe exhaust on the side of the casing. If this were all, the valve wouldbear with a very heavy pressure on the valve face and this pressurewould be unbalanced with respect to the axis, that is to say it would bevery much greater on the side of the axis where the exhaust port islocated than on the side of the axis where the supply port is located.To balance the valve there is a balancing port 28 cut through it fromthe pressure face to the valve face and opening upon the valve face at aradius greater than the radius of the ports therein. The function of thebalancing port is to balance the fluid pressure exerted at the valveface by the supply so that this pressure is balanced about the axis ofthe valve and also to reduce the net pressure exerted by the metal ofthe valve 21 upon the valve face. As the balancing port is at a greaterradius from the axis than the fluid supply port or main port of thevalve, the area of the balancing port can be smaller than the area ofthe main port. The total area of the two ports is somewhat smaller thanthe area of the pressure face on the back of the valve.

At the other end or" the casing the hydraulic pump is located. This endof the casing is bored out to receive a block 36 which will be calledthe pump plunger block. The pump plunger block contains five bores,coaxial with the bores of the pistons in the engine cylinder block. Eachbore in the pump plunger block contains a hardened steel hydrauliccylinder 31 bored out and lapped to fit a plunger 16 having a ball headto fit the socket in the corresponding piston above described. Eachcylinder has a flange at its rear end which overlies the rear surface ofthe pump cylinder block and serves to locate the cylinder therein.Outside the pump cylinder block there is a plug 32 which extends acrossthe end of the casing and is held in place therein by a split ring 132.The space 130 between the plug 32 and the outer face of the pumpcylinder block constitutes a delivery chamber for the pump. Each of thepump cylinders has an axial delivery port in its end which opensinto-the pump delivery chamber and contains a ball delivery valve 131held on its seating when not open by a fiat spring 133 in the pumpdelivery chamher. The same spring acts for all the pumps and consists ofa steel sheet stamping having a centre portion surrounded by five radialspring arms to bear on the delivery valves of all the pumps. The inletports for the pumps are cut in the sides of the pump barrels and areuncovered by the plungers when these are drawn out of their cylinders bythe pistons of the engine portion of the mechanism. They are connectedby radial passages 33 to a central suction opening 37, which latter isconnected by a nipple and appropriate pipework to thesupply. Thedelivery of the pump is taken to another nippic 35 which is secured inthe plug which encloses the pump delivery chamber.

Referring now to Figures 3 to 5, the unit comprises a cylindrical motorcylinder body 4t} externally gilled at it for cooling purposes andcontaining five parallel motor cylinder bores 42 fitted with liners 43.On the end of the body are studs M which carry nuts 45 serving to holdin place a cylinder head'46 and an exhaust flange 47. In the cylinders42 work pistons which are hollow and fitted with plugs 52 to bear on theheads 53 of pump rams 51' The rams 5?. work in liners 54 in a pump body55. The pumpbody 55 is let into a cylindrical re- .4 cess in the end ofthe motor cylinder body 40 and is held in place by an end cap 56 andscrewed sleeve 57.

The pump body 55 contains a ball race 58 for a swash plate spindle 59 onwhich is an inclined ball-bearing swash plate 60. The spindle 59 is alsosupported by a needle roller bearing 61 in the motor cylinder block 40.The swash plate 60 engages beneath the heads 53 of the pump rams 51 andthe undersides of the heads are bevelled to suit it. The ball bearing 58is made to take end thrust as well as side thrust, so as to support theswash plate against the pressure of the motor pistons 52 and to hold thepump rams against the pistons.

On the end of the spindle 5d are dogs 62 which drive a cylindrical valve63 working in the cylinder head 46. The head carries a female screwthread 64- to receive a nipple on an air supply pipe (not shown) and theair pressure presses the valve 63 toward the spindle 59, the pressurebeing transmitted through a ball 65 and being supported by the thrustrace 58 already referred to. The valve 63 has a bore 66 and lateral port67 through which air reaches in turn each of five ports 68 cut in thehead 46 and leading to the cylinders 42. On the opposite side to theport 67 the valve 63 has an exhaust port 69, which likewise co-operateswith the ports 68 in the head and extends along the valve body 63 as faras an exhaust port 70 cut in the head and leading to an exhaust passage71 in the exhaust flange 47. The passage 71 communicates with a screwedsocket 72 for an exhaust pipe connection (not shown).

As will be evident the valve 63 must be timed, by engaging it with thedog 62 correctly, relatively to the swash plate 60, so that the airsupply reaches the cylinders 42 through ports 67, 68 at the time whenthe swash plate allows the pistons 50 to move outward under the pressureand so that they can exhaust through ports 68, 69 when moving backagain.

Spring press plungers 75 bear on the ends of the barrels 54 of the pumpsand act as discharge valves. The barrels at the ends where the valves 75bear upon them are spaced a little from the end cap 56 in which thevalves work and this permits the discharge hydraulic fluid to enter anannular space 76 between the end cap 56 and the pump body 55. Adischarge port 77 in the end cap is provided with a screwed aperture 73for connection to a delivery pipe. There is a screwed aperture 79 forconnection to a suction pipe. This leads into a central suction chamber80 which is connected by inclined ports 81 to inlet ports 82 in thewalls of the pump barrels 54. The ports 82 are uncovered by the plungers51 when these reach the inner ends of their stroke.

It will be seen that the general construction of this pump is similar tothat of Figures 1 and 2, but the cylindrical valve 63 is preferred tothe face valve 21 of Figure 2.

In either pump all the parts are extremely simple in construction.

The relative sizes of the pistons and the plungers driven thereby aresuch that if the casing is supplied at one end with air, steam or gasunder pressure at one thousand pounds per square inch the hydraulic pumpwill deliver at four thousand pounds per square inch and even with acasing which is less than three inches in diameter there will be adelivery at this pressure of four cubic inches of hydraulic fluid to thesystem per second, that is to say, nearly 1 gallon per minute. Such adevice constitutes a valuable source of pressure for use in a guidedmissile for the purpose of controlling the guideplane surfaces.

Iclaim:

l. A combined fluid pressure driven prime mover and hydraulic pump unitcomprising in combination a block of motor cylinders closed at one endexcept for ports and open at the other end, said cylinders being groupedaround an axis and extending longitudinally relatively thereto, a blockof pump cylinders similarly grouped around the axis and closed exceptfor ports at the opposite end from the motor cylinders, suction anddelivery valve means to and from said pump cylinders, pistons in themotor and pump cylinders, each motor piston being directly engaged withone of the pump pistons, a swash-plate located between the two groups ofcylinders, rotatable about said axis and operatively connected to themotor pistons to be driven thereby, a spindle for the swash-plateextending along said axis between the motor pistons, a rotary valveclose to the closed ends of the motor pistons coaxial with and driven bythe spindle, and ports controlled by said rotary valve directlycommunicating with the closed ends of the motor cylinders and a fluidpressure supply distinct from the pump supply and delivery connection tosaid rotary valve.

2. A unit as claimed in claim 1 wherein the motor cylinders are locatedin a motor cylinder body parallel with and grouped around the axisthereof, which body is hollowed out at one end to receive and enclose apump body containing the pump cylinders.

3. A unit as claimed in claim 2 wherein the motor cylinder body and pumpbody each contain a bearing for the swash plate spindle.

4. A unit as claimed in claim 1 wherein the rotary valve has a pressureface on the opposite side thereof from the valve face of the cylinderblock, a main supply port extends through the valve from inside thepressure face to the valve face, and is located on one side of the axisso as to cooperate with the ports in the cylinder block the rotary valvehaving also a balancing port lying on the other side of its axis andextending through it but opening on to the valve face of the cylinderblock at a different radius from the radius of the ports therein.

5. A combined fluid-pressure driven prime mover and hydraulic pump unitcomprising in combination a block of motor cylinders grouped around anaxis and extending longitudinally relatively thereto, a motor cylinderhead detachable from said block closing the ends of said motor cylindersand containing ports communicating therewith, an axial bore in said headinto which said ports open, an axial supply port for working fluid underpressure in said head and communicating with said bore a block of pumpcylinders similarly grouped about said axis, a supply and deliveryconnection to the pump cylinders, pistons in the motor and pumpcylinders, each motor piston being directly engaged with a pump piston,a swash plate located around said axis between the motor and pumpcylinders and operatively connected to the motor pistons, a swash platespindle extending along said axis through the motor cylinder block and arotary motor-valve on said spindle and fitting in said bore forcontrolling said ports in the motor cylinder head and a fluid pressuresupply to said rotary valve distinct from the supply and deliveryconnection to said pump cylinders.

6. A unit as claimed in claim 5 including an exhaust port passingthrough the cylinder head which is controlled by the rotary motor-valve,an exhaust flange backing up said cylinder head, and an exhaust passageand an exhaust pipe connection in said flange communicating with saidexhaust port.

7. A unit as claimed in claim 6 wherein the rotary motor-valve is acylindrical valve having a fluid pressure supply passageway extendingaxially therethrough, a radial port in the wall of said cylindricalvalve opening from said passageway which is adapted to be placed incommunication with said motor cylinder ports, and an exhaust passagewhich is adapted to be placed in communication with said motor cylinderports, said radial port and said exhaust passage communicating withdifferent ones of said ports at a time.

References Cited in the file of this patent UNITED STATES PATENTS2,070,880 Blum Feb. 16, 1937 2,114,076 Golz Apr. 12, 1938 2,243,978Reader June 3, 1941 2,356,917 Chouings Aug. 29, 1944 FOREIGN PATENTS163,857 Great Britain June 2, 1921

